Who are the 4 Kings on a deck of playing cards?

Did you know that the 4 kings on a deck of playing cards each represent a specific historic figure? According to stories, each of the 4 kings in a deck of cards represents a great ruler of the past. The King of Spades is said to be David, King of Israel; the king of Clubs is supposed to be Alexander the Great; the king of Hearts, the French King Charlemagne; and the king of Diamonds is the Roman Caesar Augustus.

However, there's still some controversy about whether these Kings are really supposed to represent someone or not. Historians say that there are not enough evidence to prove that the kings on playing cards really represent somebody. According to them, the origins of the playing cards are still unknown with the Chinese, Persians and Indians all claiming that it all started with them. Furthermore, there are periods in history that prohibits the use of these cards and playing other games of chance and people didn't dared to even talk or wrote about it.